Manufacturing method for image pickup unit and image pickup unit

ABSTRACT

A manufacturing method for an image pickup unit, the method including: a step of bonding plural lens wafers, on which optical components are formed, and forming a lens unit wafer including plural lens units; a step of bonding a bending optical element wafer including plural bending optical elements to a first surface of the lens unit wafer such that the plural bending optical elements are respectively opposed to the plural lens units and forming an optical unit wafer; a step of separating and individualizing the optical unit wafer for each of the lens units and the bending optical elements and manufacturing plural optical units; and a step of respectively bonding solid-state image pickup devices to emission surfaces of lights of the bending optical elements of the optical units.

CROSS REFERENCE TO RELATED APPLICATION

This application is a divisional application of U.S. patent applicationSer. No. 14/456,560 filed on Aug. 11, 2014, which is a continuationapplication of U.S. patent application Ser. No. 12/574,157 filed on Oct.6, 2009, now U.S. Pat. No. 8,823,859 B2, which claims the benefit ofJapanese Patent Application No. 2008-262070 filed in Japan on Oct. 8,2008 and Japanese Patent Application No. 2008-264503 filed in Japan onOct. 10, 2008, the entire contents of each of which are incorporatedherein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an image pickup unit, an optical unit,and a manufacturing method for the image pickup unit.

2. Description of the Related Art

An electronic endoscope, a cellular phone with camera, a digital camera,and the like including an image pickup unit provided with a solid-stateimage pickup device such as a CCD or a CMOS are being widely spread.

A main section of the image pickup unit includes the solid-state imagepickup device and an optical unit including a lens for making an opticalimage of a subject incident on a light receiving section of thesolid-state image pickup device. In the cellular phone with camera andthe digital camera reduced in size and thickness or the electronicendoscope adapted to view sideways and reduced in diameter of aninsertion section, for the purpose of, for example, bending an opticalaxis or realizing a reduction in thickness of the image pickup unit, theoptical unit further includes a bending optical element such as a prism.The image pickup unit in which the optical unit includes the bendingoptical element is disclosed in, for example, Japanese Utility ModelLaid-Open No. Hei 7-24088.

As shown in FIG. 1, a main section of an image pickup unit 65 disclosedin Japanese Utility Model Laid-Open No. Hei 7-24088 includes an opticalunit 68 and a solid-state image pickup device 64. A main section of theoptical unit 68 includes a lens unit 62 and a prism 63. A main sectionof the lens unit 62 includes a lens barrel 62 c, a first lens unit 62 aand a second lens unit 62 b including plural lenses provided in the lensbarrel 62 c, and a coupling frame 62 d fit in an outer circumference ona rear end side in an optical axis direction of the lens barrel 62 c.

An incident surface 63 a of the prism 63 is bonded and fixed to a rearend in the optical axis direction of the coupling frame 62 d. Thesolid-state image pickup device 64 is fixed to an emission surface 63 cof the prism 63.

In the image pickup unit 65 having such a configuration, adjustment ofan angle of deviation and centering of an optical system in the opticalunit 68 can be realized by alignment adjustment of the two lens units 62a and 62 b, the prism 63, and the solid-state image pickup device 64.

However, in the image pickup unit disclosed in Japanese Utility ModelLaid-Open No. Hei 7-24088, when the optical unit 68 and the image pickupunit 65 are manufactured, after the prism 63 and the lens unit 62 areseparately formed, the prism 63 is bonded to a rear end portion of thecoupling frame 62 d of the lens unit 62. Since work for adjusting theangle of deviation and the centering of the optical system in theoptical unit 68 is difficult and takes long time, the work causes anincrease in cost. There is a demand for a manufacturing method that canmanufacture a large number of optical units and image pickup units at atime at low cost.

On the other hand, a main section of the image pickup unit includes thesolid-state image pickup device and an optical unit including a lens formaking an optical image of a subject incident on a light receivingsection of the solid-state image pickup device. In recent years, as theoptical unit, an optical unit in which optical components are laminatedin plural layers is well known. The optical unit is formed by slicing anoptical unit wafer after bonding plural lens wafers, which form theoptical components such as a lens, a stop, and a spacer, and forming theoptical unit wafer.

As the image pickup unit, an image pickup unit is well known which isformed by slicing an image pickup unit wafer after bonding plural lenswafers, which form the optical components such as a lens, a stop, and aspacer, and forming an optical unit wafer and further bonding a sensorwafer including a solid-state image pickup device to the optical unitwafer and forming the image pickup unit wafer.

For example, Japanese Patent Application Laid-Open Publication No.2004-29554 discloses an image pickup unit 224 formed by, as shown inFIG. 2, bonding an image pickup device 223 to a bottom surface of anoptical unit 222 formed by laminating lenses 222 a to 222 c as opticalcomponents in plural layers to have spaces in an optical axis directionin a part between the lenses 222 a and 222 b and between the lenses 222b and 222 c.

In the optical unit 222 shown in FIG. 2, the optical unit 222 is formedby cutting an optical unit wafer by dicing or the like after bonding alens wafer including the lens 222 a, a lens wafer including the lens 222b, and a lens wafer including the lens 222 c and forming the opticalunit wafer. As an external shape of the optical unit 222, as shown inFIG. 2, a planar shape viewed from above is often a square shape or apolygonal shape because of a limitation in a processing method.

In the optical unit 222 disclosed in Japanese Patent ApplicationLaid-Open Publication No. 2004-29554, an area functioning as an opticallens, i.e., an area functioning to focus an optical image of a subjecton the image pickup device 223 in the optical unit 222, in other words,an area through which a light beam from the subject passes is set to adimension equal to or smaller than a dimension of a circle C inscribedin a square forming an external shape of the optical unit 222 as shownin FIG. 2 in a state of plan view from above.

Therefore, as explained above, since the external shape of the opticalunit 222 is formed in the square shape or the like because of thelimitation in the processing method, as shown in FIG. 2, an area D as anouter circumferential area of the circle C is an optically ineffectivearea in the state of plan view from above. Therefore, a useless area isformed in the optical unit 222.

As shown in FIGS. 3 and 4, in general, in an insertion section distalend 231 of an endoscope, besides an image pickup unit 234, a light guide235 for illumination, a treatment instrument inserting-through channel236, and the like are provided around the image pickup unit 234. Asshown in FIG. 4, an external dimension of the insertion section distalend 231 of the endoscope is determined by an external shape of the imagepickup unit 234 itself and an external shape of the light guide 235 forillumination and the treatment instrument inserting-through channel 236.However, even in this case, if an optically ineffective area E is formedin the image pickup unit 234, the external shape of the image pickupunit 234 is increased in size. Therefore, the insertion section distalend 231 of the endoscope is increased in diameter. This may be a causeof pain for a patient.

SUMMARY OF THE INVENTION

A manufacturing method for an image pickup unit according to a firstembodiment of the present invention, the method comprising: a step ofbonding plural lens wafers, on which optical components are formed, andforming a lens unit wafer including plural lens units; a step of bondinga bending optical element wafer including plural bending opticalelements to a first surface of the lens unit wafer such that the pluralbending optical elements are respectively opposed to the plural lensunits and forming an optical unit wafer; a step of separating andindividualizing the optical unit wafer for each of the lens units andthe bending optical elements and manufacturing plural optical units; anda step of respectively bonding solid-state image pickup devices toemission surfaces of lights of the bending optical elements of theoptical units.

An image pickup unit according to a second embodiment of the presentinvention, the image pickup unit being manufactured with themanufacturing method according to the first embodiment of the presentinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic partial sectional view of a configuration of aconventional image pickup unit;

FIG. 2 is a schematic perspective view of the configuration of theconventional image pickup unit;

FIG. 3 is a schematic partial sectional view of a configuration of aninsertion section distal end side in a state in which the conventionalimage pickup unit is provided at a distal end of an insertion section ofan endoscope;

FIG. 4 is a plan view of FIG. 3 viewed from an X direction;

FIG. 5 is a top view of an optical unit according to a first embodimentof the present invention;

FIG. 6 is a sectional view of the optical unit taken along VI-VI line inFIG. 5;

FIG. 7 is a sectional view of a configuration of a modification of theoptical unit shown in FIG. 6;

FIG. 8 is a top view of an image pickup unit according to the firstembodiment;

FIG. 9 is a sectional view of the image pickup unit taken along IX-IXline in FIG. 8;

FIG. 10 is a partial sectional view of a lens unit wafer;

FIG. 11 is a partial sectional view of a state in which a bendingoptical element wafer is bonded to a first surface of the lens unitwafer shown in FIG. 10 to form an optical unit wafer;

FIG. 12 is a partial sectional view of a state in which a sensor waferis bonded to a second surface of the lens unit wafer shown in FIG. 11 toform an image pickup unit wafer;

FIG. 13 is a partial sectional view of a state in which dicing lines areformed for respective lens units on the image pickup unit wafer shown inFIG. 12;

FIG. 14 is a partial sectional view of a state in which plural imagepickup units are individualized from the image pickup unit waferstarting from the dicing lines shown in FIG. 13;

FIG. 15 is a top view of an optical unit according to a secondembodiment of the present invention;

FIG. 16 is a sectional view of the optical unit taken along XVI-XVI linein FIG. 15;

FIG. 17 is a top view of an image pickup unit according to the secondembodiment;

FIG. 18 is a sectional view of the image pickup unit taken alongXVIII-XVIII line in FIG. 17;

FIG. 19 is a partial sectional view of a lens unit wafer;

FIG. 20 is a partial sectional view of a state in which a bendingoptical element wafer is bonded to a first surface of the lens unitwafer shown in FIG. 19 to form an optical unit wafer;

FIG. 21 is a partial sectional view of a state in which plural opticalunits are individualized from the optical unit wafer shown in FIG. 20;

FIG. 22 is a perspective view of an endoscope apparatus including anendoscope provided with an optical unit or an image pickup unit;

FIG. 23 is a perspective view of an image pickup unit according to athird embodiment of the present invention;

FIG. 24 is a sectional view of the image pickup unit taken alongXXIV-XXIV line in FIG. 23;

FIG. 25 is a sectional view of an image pickup unit according to afourth embodiment of the present invention;

FIG. 26 is an enlarged perspective view of a flat plate shown in FIG.25;

FIG. 27 is a sectional view of an image pickup unit according to a fifthembodiment of the present invention; and

FIG. 28 is a sectional view of a configuration of a modification of theimage pickup unit according to the fifth embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments of the present invention are explained below with referenceto the accompanying drawings.

First Embodiment

First, a configuration of an optical unit manufactured by amanufacturing method for an optical unit according to a first embodimentof the present invention is explained with reference to FIGS. 5 and 6.As shown in FIGS. 5 and 6, a main section of an optical unit 1 includesa lens unit 2 and a bending optical element 3.

The lens unit 2 forms an optical image emitted from the bending opticalelement 3 on a solid-state image pickup device 4 (see FIG. 9) explainedlater. A main section of the lens unit 2 includes a flat plate 2 aformed of a transparent member, a spacer 2 b superimposed on the flatplate 2 a and having a through hole formed in an optical path of lightbeam L of the optical image, a lens member 2 c superimposed on thespacer 2 b and having a convex convex lens 2 c 1 located in the opticalpath of the light beam L, a stop 2 d superimposed on the lens member 2 cand having a through hole formed in the optical path of the light beamL, and a flat plate 2 e superimposed on the stop 2 d and formed of atransparent member. In other words, the lens unit 2 is formed bylaminating the plural optical members (2 a to 2 e). The lens unit 2 mayinclude not only one convex convex lens 2 c 1 but also plural lenses.

A first surface 2 f of the lens unit 2 forms an incident surface of thelight beam L on the lens unit 2. A second surface 2 g opposed to thefirst surface 2 f of the lens unit 2 forms an emission surface of thelight beam L from the lens unit 2. The stop 2 d may be located betweenthe flat plate 2 a and the lens member 2 c instead of the spacer 2 b.The spacer 2 b may be located between the lens member 2 c and the flatplate 2 e instead of the stop 2 d. The entire flat plates 2 a and 2 e donot need to be formed of the transparent members. Only the optical pathsof the light beam L have to be formed of the transparent members.

The bending optical element 3 includes, for example, a prism. Thebending optical element 3 is provided by bonding the emission surface 3c to an outer surface of the flat plate 2 e serving as the first surface2 f of the lens unit 2. The bending optical element 3 may include notonly the prism but also a reflecting mirror and the like.

The bending optical element 3 refracts, on an inclined plane 3 b, thelight beam L of the optical image made incident from an incident surface3 a, i.e., changes a direction of the light beam L on the inclined plane3 b and makes the light beam L incident on the lens unit 2 from theemission surface 3 c.

As shown in FIG. 7, the inclined plane 3 b may be formed as a curvedsurface 3 b′. In this case, since the curved surface 3 b′ functions as aconvex lens, as shown in FIG. 7, a lens of the lens member 2 c of thelens unit 2 may be a plano-convex lens 2 c 1′ rather than the convexconvex lens 2 c 1. Therefore, a material of the lens member 2 c can bereduced from that in the configuration shown in FIG. 6.

In the optical unit 1 having such a configuration, incident light beam Lfrom a subject image is made incident on the bending optical element 3from the incident surface 3 a of the bending optical element 3,refracted on the inclined plane 3 b or the curved surface 3 b′, and thenemitted from the emission surface 3 c. The light beam L emitted from theemission surface 3 c is made incident on the lens unit 2 from the firstsurface 2 f of the lens unit 2 and emitted to the solid-state imagepickup device 4 explained later from the second surface 2 g.

A configuration of an image pickup unit manufactured by a manufacturingmethod for an image pickup unit according to the present embodiment isexplained with reference to FIGS. 8 and 9. As shown in FIGS. 8 and 9, amain section of an image pickup unit 5 includes the optical unit 1 andthe solid-state image pickup device 4. A configuration of the opticalunit 1 is the same as the configuration shown in FIGS. 5 to 7.Therefore, explanation of the configuration is omitted.

The solid-state image pickup device 4 is provided to be bonded to thesecond surface 2 g of the lens unit 2, specifically, an outer surface ofthe flat plate 2 a in a position where a light receiving section 4 areceives the light beam L emitted from the second surface 2 g of thelens unit 2.

The solid-state image pickup device 4 receives, in the light receivingsection 4 a, an optical image formed via the bending optical element 3and the lens unit 2 and performs exchange of a video signal with anexternal device via a wire piercing through a not-shown substrate thatfixes the solid-state image pickup device 4.

Manufacturing methods for the optical unit 1 and the image pickup unit 5shown in FIGS. 5 to 9 are explained with reference to FIGS. 10 to 14.

First, as shown in FIG. 10, plural lens wafers on which opticalcomponents are formed are bonded to form a lens unit wafer 12 includinga plurality of the lens units 2. Specifically, first, the lens unitwafer 12 is formed by superimposing and bonding a lens wafer 12 bincluding a plurality of the spacers 2 b on a lens wafer 12 a includinga plurality of the flat plates 2 a, superimposing and bonding a lenswafer 12 c including a plurality of the lens members 2 c on the lenswafer 12 b, superimposing and bonding a lens wafer 12 d including aplurality of the stops 2 d on the lens wafer 12 c, and superimposing andbonding a lens wafer 12 e including a plurality of the flat plates 2 eon the lens wafer 12 d. As a result, a plurality of the lens units 2including the flat plates 2 a, the spacers 2 b, the lens members 2 c,the stops 2 d, and the flat plates 2 e are formed on the lens unit wafer12.

The lens wafers 12 a to 12 d are bonded such that transparent sectionsof the flat plates 2 a and 2 e, the through holes of the spacers 2 b andthe stops 2 d, and the convex convex lenses 2 c 1 of the lens members 2c are respectively located on optical axes of light beams L.

Subsequently, as shown in FIG. 11, a bending optical element wafer 13including a plurality of the bending optical elements 3 is bonded to thefirst surface 12 f forming an incident surface of the light beam L ofthe lens unit wafer 12, specifically, an outer surface of the lens wafer12 e such that the bending optical elements 3 are respectively opposedto the lens units 2 and emission surfaces 3 c of the bending opticalelements 3 are set in contact with the lens units 2. An optical unitwafer 10 including a plurality of the optical units 1 is formed.

In this state, although not shown in the figure, if the optical unitwafer 10 is separated and individualized for each of the lens units 2,i.e., for each of the optical units 1 and the bending optical elements3, a plurality of the optical units 1 shown in FIGS. 5 and 6 aremanufactured.

When the image pickup unit 5 is manufactured, as shown in FIG. 12, asensor wafer 14 including a plurality of the solid-state image pickupdevices 4 is bonded to the second surface 12 g forming an emissionsurface of the light beam L opposed to the first surface 12 f of thelens unit wafer 12 in the optical unit wafer 10 shown in FIG. 11,specifically, an outer surface of the lens wafer 12 a such that thesolid-state image pickup devices 4 are respectively opposed to the lensunits 2. An image pickup unit wafer 15 including a plurality of theimage pickup units 5 including the optical units 1 and the solid-stateimage pickup devices 4 is formed.

Specifically, as shown in FIG. 12, the sensor wafer 14 is bonded to thesecond surface 12 g of the lens unit wafer 12 in positions where lightreceiving sections 4 a of the solid-state image pickup devices 4 receivethe light beams L emitted from the lens units 2.

Thereafter, as shown in FIG. 13, dicing lines 6 are formed in the imagepickup unit wafer 15 respectively for the lens units 2 and the bendingoptical elements 3 and the solid-state image pickup devices 4, i.e., theimage pickup units 5. As shown in FIG. 14, the image pickup unit wafer15 is separated and individualized on the basis of the dicing lines 6.Then, a plurality of the image pickup units 5 shown in FIGS. 8 and 9 aremanufactured.

In this way, in the present embodiment, the plural optical units 1 aremanufactured by bonding the plural lens wafers 12 a to 12 e, on whichthe optical components are formed, and forming the lens unit wafer 12including the plural lens unit 2, bonding the bending optical elementwafer 13 including the plural bending optical elements 3 to the firstsurface 12 f of the lens unit wafer 12 and forming the optical unitwafer 10, and individualizing the optical unit wafer 10.

The plural image pickup units 5 are manufactured by bonding the sensorwafer 14 including the plural solid-state image pickup devices 4 to thesecond surface 12 g in the lens unit wafer 12 of the optical unit wafer10 and forming the image pickup unit wafer 15 and individualizing theimage pickup unit wafer 15.

Consequently, the optical unit 1 shown in FIGS. 5 and 6 or the imagepickup unit 5 shown in FIGS. 8 and 9 is formed at a wafer level.Therefore, focus adjustlessness can be realized by adjusting andmanaging the thicknesses of the wafers that form the optical units 1 orthe image pickup units 5.

Accurate alignment adjustment can be easily performed by using a waferprocess. Therefore, work for adjusting an angle of deviation andcentering of an optical system in the optical unit 1 is substantiallyreduced. A large number of optical units 1 or the image pickup units 5can be collectively manufactured. Consequently, high yield and low costcan be realized.

As explained in a second embodiment of the present invention later, arecess or an opening (both of which are not shown in the figure) isformed in a position opposed to the light receiving section 4 a of thesolid-state image pickup device 4 on the second surface 2 g of the lensunit 2 of the optical unit 1. Then, the image pickup unit 5 can bemanufactured without spoiling a microlens effect of the solid-stateimage pickup device 4.

Consequently, it is possible to provide the manufacturing method for theoptical unit 1 and the manufacturing method for the image pickup unit 5that can reduce work for adjusting an angle of deviation and centeringof the optical system in the optical unit 1 and efficiently manufacturethe optical unit 1 and the image pickup unit 5 as well as the opticalunit 1 and the image pickup unit 5.

Second Embodiment

An optical unit and an image pickup unit according to a secondembodiment of the present invention are explained below. Configurationsof the optical unit and the image pickup unit according to the presentembodiment are different from those of the optical unit and the imagepickup unit according to the first embodiment in that a direction oflight made incident on the optical unit is opposite and the solid-stateimage pickup device is bonded to the emission surface of the bendingoptical element. Therefore, only these differences are explained.Components same as those in the first embodiment are denoted by the samereference numerals and signs and explanation of the components isomitted.

First, a configuration of an optical unit manufactured by amanufacturing method for an optical unit according to the presentembodiment is explained with reference to FIGS. 15 and 16. As shown inFIGS. 15 and 16, a main section of an optical unit 41 includes a lensunit 42 and a bending optical element 43.

The lens unit 42 forms an optical image on a solid-state image pickupdevice 44 (see FIG. 18) explained later via the bending optical element43. A main section of the lens unit 42 includes a flat plate 42 a formedof a transparent member, a spacer 42 b superimposed on the flat plate 42a and having a through hole formed in an optical path of light beam L ofthe optical image, a lens member 42 c superimposed on the spacer 42 band having a convex convex lens 42 c 1 located in the optical path ofthe light beam L, a stop 42 d superimposed on the lens member 42 c andhaving a through hole formed in the optical path of the light beam L,and a flat plate 42 e superimposed on the stop 42 d and formed of atransparent member. In other words, the lens unit 42 is formed bylaminating the plural optical members (42 a to 42 e). The lens unit 42may include not only one lens 42 c 1 but also plural lenses.

A first surface 42 f of the lens unit 42 forms an emission surface ofthe light beam L from the lens unit 42. A second surface 42 g opposed tothe first surface 42 f of the lens unit 42 forms an incident surface ofthe light beam L on the lens unit 42.

The stop 42 d may be located between the flat plate 42 a and the lensmember 42 c instead of the spacer 42 b. The spacer 42 b may be locatedbetween the lens member 42 c and the flat plate 42 e instead of the stop42 d. The entire flat plates 42 a and 42 e do not need to be formed ofthe transparent members. Only the optical paths of the light beam L haveto be formed of the transparent members.

The bending optical element 43 includes, for example, a prism. Thebending optical element 43 is provided by bonding an incident surface 43c to an outer surface of the flat plate 42 e serving as the firstsurface 42 f of the lens unit 42. The bending optical element 43 is mayinclude not only the prism but also a reflecting mirror and the like.

The bending optical element 43 refracts, on an inclined plane 43 b, thelight beam L of the optical image made incident from the first surface42 f of the lens unit 42, i.e., changes a direction of the light beam Lon the inclined plane 43 b and makes the light beam L incident on thesolid-state image pickup device 44 from an emission surface 43 a. Theinclined plane 43 b may be formed as a curved surface as shown in FIG.7.

A recess 43 d is formed in the emission surface 43 a of the bendingoptical element 43. An optical surface 43 dt is formed on a bottomsurface of the recess 43 d. The light beam L is also emitted from theoptical surface 43 dt.

In the optical unit 41 having such a configuration, incident light beamL from a subject image is made incident on the lens unit 42 from thesecond surface 42 g, made incident on the bending optical element 43from the first surface 42 f via the incident surface 43 c, refracted onthe inclined plane 43 b, and then emitted from the emission surface 43a. The light beam L emitted from the emission surface 43 a is madeincident on the solid-state image pickup device 44 explained later.

A configuration of an image pickup unit manufactured by a manufacturingmethod for an image pickup unit according to the present embodiment isexplained with reference to FIGS. 17 and 18.

As shown in FIGS. 17 and 18, a main section of an image pickup unit 45includes the optical unit 41 and the solid-state image pickup device 44.A configuration of the optical unit 41 is the same as the configurationshown in FIGS. 15 and 16. Therefore, explanation of the configuration isomitted.

The solid-state image pickup device 44 is provided to be bonded to theemission surface 43 a of the bending optical element 43 after beingaligned in a position where a space is formed between a light receivingsection 44 a and the optical surface 43 dt and the light receivingsection 44 a receives the light beam L emitted from the optical surface43 dt.

The solid-state image pickup device 44 receives, in the light receivingsection 44 a, an optical image formed via the lens unit 42 and thebending optical element 43 and performs exchange of a video signal withan external device via a not-shown wire electrically connected to anelectrode 44 b of the solid-state image pickup device 44.

Manufacturing methods for the optical unit 41 and the image pickup unit45 shown in FIGS. 15 to 18 are explained with reference to FIGS. 19 to21.

First, as shown in FIG. 19, plural lens wafers on which opticalcomponents are formed are bonded to form a lens unit wafer 12′ includinga plurality of the lens units 42. Specifically, first, the lens unitwafer 12′ is formed by superimposing and bonding a lens wafer 12 b′including a plurality of the spacers 42 b on a lens wafer 12 a′including a plurality of the flat plates 42 a, superimposing and bondinga lens wafer 12 c′ including a plurality of the lens members 42 c on thelens wafer 12 b′, superimposing and bonding a lens wafer 12 d′ includinga plurality of the stops 42 d on the lens wafer 12 c′, and superimposingand bonding a lens wafer 12 e′ including a plurality of the flat plates42 e on the lens wafer 12 d′. As a result, a plurality of the lens units42 including the flat plates 42 a, the spacers 42 b, the lens members 42c, the stops 42 d, and the flat plates 42 e are formed on the lens unitwafer 12′.

The lens wafers 12 a′ to 12 d′ are bonded such that transparent sectionsof the flat plates 42 a and 42 e, the through holes of the spacers 42 band the stops 42 d, and the lenses 42 c 1 of the lens members 42 c arerespectively located on optical axes of light beams L.

Subsequently, as shown in FIG. 20, a bending optical element wafer 13′including a plurality of the bending optical elements 43 is bonded to afirst surface 12 f forming an emission surface of the light beam L ofthe lens unit wafer 12′, specifically, an outer surface of the lenswafer 12 e′ such that the bending optical elements 43 are respectivelyopposed to the lens units 42 and incident surfaces 43 c of the bendingoptical elements 43 are set in contact with the lens units 42. Anoptical unit wafer 10′ including a plurality of the optical units 41 isformed.

Subsequently, as shown in FIG. 21, when the optical unit wafer 10′ isseparated and individualized for each of the lens units 42 and thebending optical elements 43, i.e., for each of the optical units 41, aplurality of the optical units 41 shown in FIGS. 15 and 16 aremanufactured.

Finally, when the image pickup unit 45 is manufactured, as shown in FIG.18, the solid-state image pickup devices 44 are respectively aligned andadjusted and bonded to the emission surfaces 43 a of the bending opticalelements 43 of the individualized optical units 41.

Specifically, the solid-state image pickup devices 44 are respectivelybonded to the emission surfaces 43 a in positions where spaces areformed between the light receiving sections 44 a and the opticalsurfaces 43 dt and the light receiving sections 44 a receive the lightbeams L emitted from the optical surfaces 43 dt. As a result, aplurality of the image pickup units 45 shown in FIGS. 17 and 18 aremanufactured.

With such a configuration, since the solid-state image pickup device 44is individually bonded, work efficiency falls from that in the firstembodiment. Otherwise, effects same as those in the first embodiment canbe obtained. Besides, the solid-state image pickup device 44 is joinedto the emission surface 43 a of the bending optical element 43 with aspace formed on the light receiving section 44 a of the solid-stateimage pickup device 44. Therefore, the solid-state image pickup device44 can be formed without spoiling an effect of a microlens used forimproving the performance of the image pickup unit 45. Since the bendingoptical element 43 is arranged on the solid-state image pickup device44, a degree of freedom in optical design is improved. Compared with thefirst embodiment, the image pickup unit 45 can be formed low in height.

The optical unit or the image pickup unit explained in the first andsecond embodiments is provided in, for example, an endoscope.

As shown in FIG. 22, an endoscope apparatus 101 includes an endoscope102 and a peripheral apparatus 100. A main section of the endoscope 102includes an operation section 103, an insertion section 104, and auniversal cord 105.

A main section of the peripheral apparatus 100 includes a light sourcedevice 121, a video processor 122, a connection cable 123, a keyboard124, and a monitor 125 arranged on a rack 126. The endoscope 102 and theperipheral apparatus 100 having such configurations are connected toeach other by a connector 119.

The insertion section 104 of the endoscope 102 includes a distal endportion 106, a bending portion 107, and a flexible tube portion 108. Anobject lens 111 is disposed on a side surface of the distal end portion106. The image pickup unit 5 or the image pickup unit 45 is incorporatedin the distal end portion 106.

The connector 119 is provided at the distal end of the universal cord105 of the endoscope 102. The connector 119 is connected to the lightsource device 121 of the peripheral apparatus 100. A not-shown lightguide cap forming an end of a not-shown light guide, an electric contactsection to which an end of a not-shown image pickup cable is connected,and the like are disposed in the connector 119.

The image pickup cable is inserted from the solid-state image pickupdevice 4 or the solid-state image pickup device 44 in the distal endportion 106 to the electric contact section in the connector 119 throughthe insertion section 104, the operation section 103, and the universalcord 105. The image pickup cable transmits an electric signal of animage picked up by the solid-state image pickup device 4 or thesolid-state image pickup device 44 to the video processor 122.

As explained above, if the optical unit or the image pickup unitexplained in the first and second embodiments is provided in the distalend portion of the insertion section of the endoscope, the distal endportion can be further reduced in diameter.

The optical unit or the image pickup unit explained in the first andsecond embodiments may be applied not only to the endoscope but also toa cellular phone with camera and a digital camera.

As explained above, according to the present invention illustrated inthe first and second embodiments, it is possible to reduce work foradjusting an angle of deviation and centering of an optical system in anoptical unit. Further, it is possible to provide a manufacturing methodfor an optical unit and a manufacturing method for an image pickup unitthat can reduce work for adjusting an angle of deviation and centeringof an optical system in an optical unit and efficiently manufacture anoptical unit or an image pickup unit and provide an optical unit and animage pickup unit manufactured by the manufacturing methods.

In other words, since an optical unit or an image pickup unit is formedat a wafer level, focus adjustment is made unnecessary by adjusting andmanaging the thickness of a wafer forming the optical unit or the imagepickup unit. Further, accurate alignment can be easily performed byusing a wafer process. Therefore, work for adjusting an angle ofdeviation, centering, and the like of an optical system in the opticalunit is substantially reduced and a large number of optical units orimage pickup units can be collectively formed. Therefore, it is possibleto realize high yield and low cost.

The present invention illustrated in the first and second embodimentsare as explained below.

(1) A manufacturing method for an optical unit including:

a step of bonding plural lens wafers, on which optical components areformed, and forming a lens unit wafer including plural lens units;

a step of bonding a bending optical element wafer including pluralbending optical elements to a first surface of the lens unit wafer suchthat the plural bending optical elements are respectively opposed to theplural lens units and forming an optical unit wafer; and a step ofseparating and individualizing the optical unit wafer for each of thelens units and the bending optical elements and manufacturing pluraloptical units.

(2) A manufacturing method for an image pickup unit including:

a step of bonding plural lens wafers, on which optical components areformed, and forming a lens unit wafer including plural lens units;

a step of bonding a bending optical element wafer including pluralbending optical elements to a first surface of the lens unit wafer suchthat the plural bending optical elements are respectively opposed to theplural lens units and forming an optical unit wafer;

a step of bonding a sensor wafer including plural solid-state imagepickup devices to a second surface opposed to the first surface of thelens unit wafer in the optical unit wafer such that the pluralsolid-state image pickup devices are respectively opposed to the plurallens units and forming an image pickup unit wafer; and

a step of separating and individualizing the image pickup unit wafer foreach of the lens units, the bending optical elements, and thesolid-state image pickup devices and manufacturing plural image pickupunits.

(3) The manufacturing method for an image pickup unit according to (2)above, wherein

the first surface of the lens unit wafer forms incident surfaces oflight beams on the respective lens units, and

the step of forming an image pickup unit wafer is bonding the sensorwafer to the second surface, which forms emission surfaces of lightbeams from the respective lens units of the lens unit wafer, inpositions where light receiving sections of the respective solid-stageimage pickup devices receive light beams emitted from the respectivelens units.

(4) A manufacturing method for an image pickup unit including:

a step of bonding plural lens wafers, on which optical components areformed, and forming a lens unit wafer including plural lens units;

a step of bonding a bending optical element wafer including pluralbending optical elements to a first surface of the lens unit wafer suchthat the plural bending optical elements are respectively opposed to theplural lens units and forming an optical unit wafer;

a step of separating and individualizing the optical unit wafer for eachof the lens units and the bending optical elements and manufacturingplural optical units; and

a step of respectively bonding solid-state image pickup devices toemission surfaces of light beams of the bending optical elements of therespective optical units.

(5) The manufacturing method for an image pickup unit according to (4)above, wherein

recesses are respectively formed in the emission surfaces of therespective bending optical elements and optical surfaces arerespectively formed on bottom surfaces of the recesses, and

the step of bonding solid-stage image pickup devices is bonding thesolid-state image pickup devices in positions where spaces are formedbetween the respective light receiving section of the solid-state imagepickup devices and the optical surfaces of the bending optical elementsand the light receiving sections receive light beams emitted from therespective optical surfaces.

(6) The manufacturing method for an image pickup unit according to (4)or (5) above, wherein

the first surface of the lens unit wafer forms emission surfaces oflight beams from the respective lens units, and

the step of forming an optical unit wafer is bonding the bending opticalelement wafer to the emission surfaces of the lens unit wafer.

(7) An optical unit manufactured by the manufacturing method for anoptical unit according to (1) above.

(8) An image pickup unit manufactured by the manufacturing method for animage pickup unit according to any one of (2) to (6) described above.

(9) An endoscope including the optical unit according to (7) above.

(10) An endoscope including the image pickup unit according to (8)above.

Third Embodiment

An optical unit and an image pickup unit according to a third embodimentof the present invention are explained below. As shown in FIGS. 23 and24, a main section of an image pickup unit 201 according to the presentembodiment includes an image pickup device 202 and an optical unit 203.

A main section of the optical unit 203 includes a flat plate 217 as anoptical component, a spacer member 208 as an optical component bonded onthe flat plate 217, a flat plate 218 as an optical component bonded onthe spacer member 208, a stop 207 as an optical component bonded on theflat plate 218, and a flat plate 219 as an optical component bonded onthe stop 207. In other words, the optical unit 203 is formed as alaminated body formed by bonding the plural optical components 217 to219, 207, and 208.

The stop 207 may be provided between the flat plate 217 and the flatplate 218. The spacer member 208 may be provided between the flat plate218 and the flat plate 219. Further, the spacer member 208 does not haveto be provided.

The flat plate 217 has an image pickup lens 217 a in a first area 261 ina state of plan view from above of the optical unit 203, for example,the center area. The flat plate 217 is formed of a transparent member,for example, glass.

The flat plate 218 has an image pickup lens 218 a in the first area 261and has, for example, four illumination lenses 218 b in second areas 262that avoid the first area 261 in the state of plan view from above ofthe optical unit 203, for example, a peripheral area of the first area261. The flat plate 218 is formed of a transparent member, for example,glass. The second areas 262 are areas other than an area where a lightbeam from a subject passes in the optical unit 203. Specifically, thecenter area in the state of plan view from above of the optical unit 203is the first area 261 having a substantially circular shape. Areas otherthan the first area 261 are the second areas 262. When the state of planview from above of the optical unit 203 is a rectangular shape, it isdesirable that the illumination lenses 218 b are respectively arranged,in particular, at four corners in the second areas 262. It goes withoutsaying that only one illumination lens 218 b may be provided.

The flat plate 219 has an image pickup lens 219 a in the first area 261and has, for example, four illumination lenses 219 b in the second areas262. The flat plate 219 is made of a transparent member, for example,glass. The image pickup lenses 217 a to 219 a are provided to be opposedto one another in a laminating direction S of the optical components 217to 219, 207, and 208 in the first area 261. The illumination lenses 218b and 219 b are provided to be opposed to one another in the laminatingdirection S in the second areas 262.

Specifically, in the optical unit 203, an image pickup optical section Ahaving the image pickup lenses 217 a, 218 a, and 219 a is formed alongthe laminating direction S in the first area 261. Illumination opticalsections B having the illumination lenses 218 b and 219 b are formedalong the laminating direction S in the second areas 262.

The flat plates 217 to 219 may be formed of transparent resin or acomposite member of the transparent resin and the glass without beinglimited to be formed of glass.

The spacer member 208 sets a space in the laminating direction S betweenthe flat plate 217 and the flat plate 218 to an arbitrary dimension. Thespacer member 208 is formed of a glass plate or a resin sheet. The stop207 decides the brightness (F number) of light made incident on theimage pickup lenses 217 a to 219 a and blocks an unnecessary ray madeincident on the image pickup optical section A. The stop 207 is formedof a black resin sheet or metal plate.

As shown in FIG. 24, in the second areas 262 of the optical unit 203,first recesses 203 h are formed in the flat plate 217, the spacer member208, and the flat plate 218 from a bottom surface 203 t of the opticalunit 203 along the laminating direction S.

The image pickup device 202 including, for example, a CMOS semiconductordevice is bonded to the bottom surface 203 t of the optical unit 203 tobe integral with the optical unit 203. Specifically, the image pickupdevice 202 has an image pickup section 204 and first peripheral circuitsections 205 amounted with light emitting elements 209 including, forexample, white LEDs. The image pickup device 202 is bonded to the bottomsurface 203 t of the optical unit 203 such that the image pickup section204 is located in the first area 261, the first peripheral circuitsections 205 and the light emitting elements 209 are located in thesecond areas 262, and the light emitting elements 209 are located in thefirst recesses 203 h.

Light blocking members 210 that prevent illumination light beamsirradiated from the light emitting elements 209 from being made incidenton the image pickup optical section A is provided in the circumferentialsurface of the first recesses 203 h. Since the incidence of theillumination light beams on the image pickup optical section A iseliminated by the light blocking members 210, the image pickup section204 can acquire a high-definition image.

The illumination light beams irradiated from the light emitting elements209 are evenly expanded and irradiated to a subject in the illuminationlenses 218 b and 219 b in the illumination optical sections B. Lightemitting operation of the light emitting elements 209 is controlled by anot-shown control section outside the image pickup unit 201 insynchronization with image pickup operation of the image pickup section204.

As shown in FIG. 23, in the present embodiment, an external shape of theimage pickup device 202 and an external shape of the optical unit 203are the same. This is because, when the image pickup unit 201 ismanufactured, plural lens wafers, i.e., a lens wafer including the flatplate 217, a lens wafer including the spacer member 208, a lens waferincluding the flat plate 218, a lens wafer including the stop 207, and alens wafer including the flat plate 219 are bonded and laminated to forman optical unit wafer, a sensor wafer including the image pickup device202 is bonded to the optical unit wafer to form an image pickup unitwafer, and then the image pickup unit wafer is sliced and divided by,for example, dicing to manufacture the image pickup unit 201.

In FIG. 23, an external shape of the image pickup unit 201 is shown as asquare shape. However, the external shape of the image pickup unit 201may be a polygonal shape such as a hexagonal shape.

After the optical unit 203 is separated from the optical unit wafer, theimage pickup unit 201 may be formed by bonding the image pickup device202 separated from the sensor wafer to the optical unit 203. Further,after the image pickup device 202 is bonded to the optical unit wafer,the image pickup unit 201 may be formed by separating the image pickupdevice 202 or, after the optical unit 203 is bonded to the sensor wafer,the image pickup unit 201 may be formed by separating the optical unit203.

The external shapes of the optical unit 203 and the image pickup device202 do not need to be the same. The optical unit 203 and the imagepickup device 202 may be formed in different shapes.

As explained above, in the present embodiment, in the image pickup unit201, the image pickup optical section A is formed in the first area 261of the optical unit 203 and the illumination optical sections B areformed in the second areas 262. The image pickup section 204 is locatedin the first area 261. The first peripheral circuit sections 205 and thelight emitting elements 209 are located in the second areas 262.

Consequently, since the areas other than the image pickup opticalsection A can be used as the illumination optical sections B, it ispossible to combine illumination functions to improve the functionswithout increasing an image pickup unit in size. When the image pickupunit is provided at, for example, an insertion section distal end of anendoscope, an insertion section distal end portion can be reduced insize. When the image pickup unit is provided in a capsule endoscope, thecapsule endoscope itself can be reduced in size. Since the image pickupoptical section A and the illumination optical sections B can beintegrally manufactured in the optical unit 203, assembly and machiningcost for the image pickup unit 201 is reduced compared with theconventional ones.

Therefore, it is possible to provide an optical unit and an image pickupunit that can effectively utilize an area other than an area where alight beam from a subject passes and realize a reduction in size.

Fourth Embodiment

An optical unit and an image pickup unit according to a fourthembodiment of the present invention are explained below. Configurationsof the optical unit and the image pickup unit according to the presentembodiment are different from those of the optical unit and the imagepickup unit according to the third embodiment in that a lens having arectangular shape in plan view from above is provided on the imagepickup lens 217 a of the flat plate 217 and that a part of the secondareas 262 of the optical unit is set as a third area 263 and a radiotransmitting and receiving section is provided in the third area 263.Therefore, only these differences are explained. Components same asthose in the third embodiment are denoted by the same reference numeralsand signs and explanation of the components is omitted.

As shown in FIG. 25, a resin lens 206 having a curved surface on thesurface of a glass plane is complexly formed on the image pickup lens217 a of the flat plate 217. As shown in FIG. 26, the resin lens 206 isformed in a shape projecting in a convex shape upward from a top surfaceformed in a plane of the image pickup lens 217 a. A shape in plan viewfrom above of the resin lens 206 is a rectangular shape obtained bylinearly cutting off four directions of a circular shape to match ashape of the image pickup section 204 of the image pickup device 202.

This is because, since an external shape of the image pickup section 204of the image pickup device 202 is generally a square shape, it isdesirable to form an effective external shape of the resin lens 206 in asubstantial square shape according to a shape of a passing area of alight beam that reaches the image pickup section 204.

The resin lens 206 may be formed on the image pickup lens 218 a or onthe image pickup lens 219 a without being limited to be formed on theimage pickup lens 217 a. Further, the resin lens 206 may be formed onthe illumination lenses 218 b or on the illumination lenses 219 b.

As shown in FIGS. 25 and 26, a radio transmitting and receiving sectionG is provided in the third area 263, which is a part of the second areas262 of the optical unit 203. Because the third area 263 is a part of thesecond areas 262, the third area 263 is an area other than an area wherea light beam from a subject passes. An area where the illuminationlenses 218 b are not formed in the second areas 262 is set as the thirdarea 263. The radio transmitting and receiving section G is disposed inthe third area 263.

In the third area 263 of the optical unit 203, a second recess 203 g isformed in the flat plate 217, the spacer member 208, and the flat plate218 from the bottom surface 203 t of the optical unit 203 along thelaminating direction S.

In the present embodiment, the image pickup device 202 includes theimage pickup section 204, the first peripheral circuit sections 205mounted with the light emitting elements 209, a radio transmitting andreceiving element 211 including a transmitting and receiving antenna anda transmitting and receiving circuit formed as patterns, and a secondperipheral circuit section 255 mounted with the radio transmitting andreceiving element 211. The image pickup device 202 is bonded to thebottom surface 203 t of the optical unit 203 such that the image pickupsection 204 is located in the first area 261, the first peripheralcircuit sections 205 and the light emitting elements 209 are located inthe second areas 262, the light emitting elements 209 are located in thefirst recesses 203 h, the second peripheral circuit section 255 and theradio transmitting and receiving element 211 are located in the thirdarea 263, and the radio transmitting and receiving element 211 islocated in the second recess 203 g.

The radio transmitting and receiving element 211 can transmit an outputsignal of the image pickup device 202 to the outside by radio andcontrol the operation of the image pickup device 202 from the outside.The radio transmitting and receiving element 211 can also transmit anidentification signal peculiar to the image pickup unit 201.

Since the image pickup unit 201 according to the present embodimentincludes the radio transmitting and receiving element 211, the imagepickup unit 201 can be applied to, for example, a capsule endoscope formedial use.

In the present embodiment, the light emitting elements 209 located inthe second areas 262 is an organic EL including a thin-film luminouselement and is directly formed in the first peripheral circuit sections205 of the image pickup device 202. Light emitting operation of thelight emitting elements 209 is controlled by the first peripheralcircuit sections 205 of the image pickup device 202 in synchronizationwith image pickup operation of the image pickup device 202.

As explained above, in the present embodiment, a part of the secondareas 262 of the optical unit 203 is set as the third area 263 and theradio transmitting and receiving element 211 is provided in the thirdarea 263.

Therefore, since areas other than the image pickup optical section A ofthe optical unit 203 can be used not only as the illumination opticalsections B but also as the radio transmitting and receiving sections G,it is possible to realize a high-function small image pickup unit havingnot only an illumination function but also a radio function.

In the present embodiment, the resin lens 206 having a rectangular shapein plan view from above is formed on the image pickup lens 217 aintegrally with the image pickup lenses 217 a. Therefore, it is possibleto combine the illumination function, the radio function, and the liketo improve the functions without increasing an image pickup unit insize. For example, when the image pickup unit is provided at, forexample, an insertion section distal end of an endoscope, an insertionsection distal end section can be reduced in size and diameter. Further,when the image pickup unit is provided in a capsule endoscope, thecapsule endoscope itself can be reduced in size. Other effects of thepresent embodiment are the same as those in the third embodiment.

Fifth Embodiment

An optical unit and an image pickup unit according to a fifth embodimentof the present invention are explained below. Configurations of theoptical unit and the image pickup unit according to the presentembodiment are different from those of the optical unit and the imagepickup unit according to the fourth embodiment in that the image pickuplens 218 a of the flat plate 218 includes a Fresnel lens and that theimage pickup lens 217 a of the flat plate 217 includes an asphericallens. Therefore, only the differences are explained. Components same asthose in the fourth embodiment are denoted by the same referencenumerals and signs and explanation of the components is omitted.

As shown in FIG. 27, in the present embodiment, the image pickup lens218 a includes a Fresnel lens 259. The Fresnel lens 259 is formed bymolding transparent resin and is thin compared with a normal convexlens. The image pickup lens 218 a may include a diffractive lens withoutbeing limited to the Fresnel lens.

The image pickup lens 217 a includes an aspherical lens 256. Since theaspherical lens 256 is formed by molding glass at high temperature, acomplicated lens shape is obtained compared with the normal convex lens.The illumination lenses 218 b and 219 b may include the Fresnel lens259, the diffractive lens, or the aspherical lens 256.

The radio transmitting and receiving section G is provided in the thirdarea 263 of the optical unit 203. In the third area 263 of the opticalunit 203, a second recess 203 m is formed in the flat plate 217, thespacer member 208, and the flat plate 218 from the bottom surface 203 tof the optical unit 203 along the laminating direction S.

In the present embodiment, the image pickup device 202 includes theimage pickup section 204, the first peripheral circuit sections 205mounted with the light emitting elements 209 including, for example,white LEDs, a radio transmitting and receiving element 251 including acoil-like transmitting and receiving antenna and a transmitting andreceiving circuit, and the second peripheral circuit section 255 mountedwith the radio transmitting and receiving element 251. The image pickupdevice 202 is bonded to the bottom surface 203 t of the optical unit 203such that the image pickup section 204 is located in the first area 261,the first peripheral circuit sections 205 and the light emittingelements 209 are located in the second areas 262, the light emittingelements 209 are located in the first recesses 203 h, the secondperipheral circuit section 255 and the radio transmitting and receivingelement 251 are located in the third area 263, and the radiotransmitting and receiving element 251 is located in the second recess203 m.

The radio transmitting and receiving element 251 can transmit an outputsignal of the image pickup device 202 to the outside by radio andcontrol the operation of the image pickup device 202 from the outside.The radio transmitting and receiving element 251 can also transmit anidentification signal peculiar to the image pickup unit 201.

In the present embodiment, as in the second embodiment, the radiotransmitting and receiving element 251 transmits a signal outputted fromthe second peripheral circuit section 255 of the image pickup device 202to the outside and receives a signal from the outside and transmits thesignal to the second peripheral circuit section 255.

Since the image pickup unit 201 having the configuration explained aboveincludes the radio transmitting and receiving element 251, the imagepickup unit 201 can be applied to, for example, a capsule endoscope formedical use.

In the present embodiment, the image pickup lens 218 a includes theFresnel lens 259 and the image pickup lens 217 a includes the asphericallens 256. Consequently, optical path length in the image pickup opticalsection A can be set shorter than that in the fourth embodiment.Therefore, the image pickup unit 201 can be further reduced in size andthe performance of the image pickup optical section A can be furtherimproved. Other effects are the same as those in the fourth embodiment.

A modification of the present embodiment is explained with reference toFIG. 28. In the present embodiment explained above, the light emittingelements 209 are located in the second recesses 203 h in theillumination optical sections B. However, the present invention is notlimited to this. As shown in FIG. 28, light guides 212 may be arrangedinstead of the light emitting elements 209 in the illumination opticalsections B. Not-shown lamps are arranged on proximal end sides of thelight guides 212. The light guides 212 transmit light beams emittedaccording to light emission of the lamps to the image pickup unit 201 asillumination light beams. The transmitted illumination light beams areexpanded and irradiated to a subject in the illumination opticalsections B.

In the present configuration, as shown in FIG. 28, an external shape ofthe image pickup device 202 is set smaller than that of the optical unit203 to avoid the light guides 212. However, not-shown through holes forinsertion are formed in the image pickup device 202 or four corners ofthe image pickup device 202 are chamfered, whereby distal ends of thelight guides 212 are arranged in positions facing the illuminationoptical sections B.

In the present embodiment, the radio transmitting and receiving element251 is provided in the third area 263. However, the present invention isnot limited to this. A sensor such as an acceleration sensor, a magneticsensor, or a GPS, a motor, or an actuator such as a piezoelectricelement may be arranged in the third area 263. The same holds true inthe fourth embodiment.

The optical unit or the image pickup unit explained in the third tofifth embodiments is able to be provided in, for example, the endoscopeshown in FIG. 22. An endoscope, for example, an endoscope for obliqueview including the optical unit or the image pickup unit explained inthe third to fifth embodiments at a distal end portion of an insertionsection has a small diameter at the distal end portion.

The optical unit or the image pickup unit explained in the third tofifth embodiments may be provided in a capsule endoscope for medical useor may be applied not only to the endoscope but also to a cellular phonewith camera and a digital camera.

As explained above, according to the present invention illustrated bythe third to fifth embodiments, it is possible to provide an opticalunit, an image pickup unit, a manufacturing method for an optical unit,and a manufacturing method for an image pickup unit that can effectivelyutilize an area other than an area where a light beam from a subjectpasses and realize a reduction in size.

Specifically, the present invention illustrated in the third to fifthembodiments is as explained below.

(1) An optical unit including a laminated body including:

an image pickup optical section formed to have, in a state of plan viewfrom above of the laminated body formed by bonding plural opticalcomponents, an image pickup lens along a laminating direction of theoptical components in a first area of the laminated body; and

an illumination optical section formed to have, in the state of planview from above of the laminated body, an illumination lens along thelaminating direction in a second area set to avoid the image pickupoptical section.

(2) The optical unit according to (1) above, wherein

the image pickup lens and the illumination lens include plural lenses,and

a Fresnel lens or a diffractive lens is provided in at least one of atleast a part of the image pickup lens and at least a part of theillumination lens.

(3) The optical unit according to (1) above, wherein at least a part ofthe image pickup lens has a rectangular external shape in plan view fromabove.

(4) The optical unit according to any one of (1) to (3) above furtherincluding a radio transmitting and receiving section in a third areathat forms a part of the second area in the state of plan view fromabove of the laminated body.

(5) An image pickup unit including an optical unit and an image pickupdevice mounted with the optical unit including:

an image pickup optical section formed to have, in a state of plan viewfrom above of the optical unit including a laminated body formed bybonding plural optical components, an image pickup lens along alaminating direction of the optical components in a first area of theoptical unit;

an illumination optical section formed to have, in the state of planview from above of the optical unit, an illumination lens along thelaminating direction in a second area set to avoid the image pickupoptical section;

a first recess drilled along the laminating direction from a bottomsurface of the optical unit in the second area of the optical unit; and

the image pickup device having an image pickup section and a firstperipheral circuit section, in which a light emitting element isprovided, and bonded to the bottom surface of the optical unit such thatthe image pickup section is located in the first area, the firstperipheral circuit section and the light emitting element are located inthe second area, and the light emitting element is located in the firstrecess.

(6) The image pickup unit according to (5) above, wherein a lightblocking member is provided on a circumferential surface of the firstrecess.

(7) The image pickup unit according to (5) or (6) above furtherincluding a radio transmitting and receiving section in a third areathat forms a part of the second area in the state of plan view fromabove of the optical unit.

(8) The image pickup unit according to (7) above further including:

a second recess drilled along the laminating direction from the bottomsurface of the optical unit in the third area of the optical unit;

the image pickup device including the image pickup section, the firstperipheral circuit section, in which the light emitting element isprovided, and a second peripheral circuit section, in which a radiotransmitting and receiving element is provided, and bonded to the bottomsurface of the optical unit such that the image pickup section islocated in the first area, the first peripheral circuit section and thelight emitting element are located in the second area and the lightemitting element is located in the first recess, and the secondperipheral circuit section and the radio transmitting and receivingelement are located in the third area and the radio transmitting andreceiving element is located in the second recess.

(9) The image pickup unit according to any one of (5) to (8) above,wherein

the image pickup lens and the illumination lens include plural lenses;and

a Fresnel lens or a diffractive lens is used in at least one of at leasta part of the image pickup lens and at least a part of the illuminationlens.

(10) The image pickup unit according to any one of (5) to (9) above,wherein

the image pickup lens and the illumination lens include plural lenses;and

at least one of at least a part of the image pickup lens and at least apart of the illumination lens has a rectangular external shape in planview from above.

(11) An endoscope including the optical unit according to any one of (1)to (4) above.

(12) An endoscope including the image pickup unit according to any oneof (5) to (10) above.

Having described the preferred embodiments of the invention referring tothe accompanying drawings, it should be understood that the presentinvention is not limited to those precise embodiments and variouschanges and modifications thereof could be made by one skilled in theart without departing from the spirit or scope of the invention asdefined in the appended claims.

What is claimed is:
 1. A method comprising: bonding lens waferscomprising optical components to form a lens unit wafer comprising lensunits; bonding a bending optical element wafer comprising bendingoptical elements to a first surface of the lens unit wafer to form anoptical unit wafer such that the bending optical elements arerespectively opposed to the lens units to arrange respective inclinedplanes of the bending optical elements to be inclined relative to thefirst surface of the lens unit wafer to refract light beams emitted fromthe lens units towards respective emission surfaces of the bendingoptical elements; separating and individualizing the optical unit waferfor each of the lens units and the bending optical elements tomanufacture optical units; and respectively bonding solid-state imagepickup devices to the emission surfaces of the bending optical elementsof the optical units.
 2. The method according to claim 1, comprising:respectively forming recesses in the emission surfaces of the bendingoptical elements, wherein the emission surfaces in which the recessesare formed comprise optical surfaces; and respectively bonding thesolid-state image pickup devices to the emission surfaces of the bendingoptical elements of the optical units such that a space is formedbetween each of light receiving sections of the respective solid-stateimage pickup devices and each of the optical surfaces of the bendingoptical elements, and the solid-state image pickup devices are arrangedin positions where the light receiving sections receive respectivelights emitted from the optical surfaces.
 3. The method according toclaim 1, wherein the first surface of the lens unit wafer forms emissionsurfaces of light beams from the respective lens units, and whereinforming the optical unit wafer comprises bonding the bending opticalelement wafer to the emission surfaces of the lens unit wafer.
 4. Animage pickup unit comprising one of the solid-state image pickup devicesbonded to one of the optical units, manufactured with the methodaccording to claim 1.